The correct answer is option 3. The IUPAC name is Iron(II) sulfide. It is the less stable amorphous form. When this is powdered, it is pyrophoric or it ignites spontaneously in air. It readily reacts with hydrochloric acid producing hydrogen sulfide.
Answer:
other than the periodic table, are often arranged by their properties
Explanation:
Money, they are arranged by how big or small they are, like coins, with pennies, dimes, and quarters.
The answer is B Covalent bonds
A). 4
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